Determining Biological Sex via an Individual Marker

Eden Alin, University at Albany, State University of New York


For decades, fingerprints have been a key tool in forensic analysis for the purpose of identifying criminals. However, when deposited at a crime scene, there is often a small chance that the fingerprint will match one in the FBI’s database of millions of files called, the Automated Fingerprint Identification System, or AFIS. Beyond their unique image, fingerprints contain and may unveil far more information about an individual. In this study, a chemical assay, the Sakaguchi test, was further developed for the analysis of a single amino acid, arginine, found within fingerprint sweat. Although arginine has significantly low concentration levels, the test proved to be able to accurately determine the biological sex of the originator. Additionally, the test showed high accuracy in differentiating male from female fingerprints even when they were collected from crime scene scenario surfaces. Forensic science may be greatly advanced with the aptitude of targeting a single analyte that can be correlated to multiple attributes of the originator such as ethnicity, food habits or possible health status. This would allow for the creation of a profile containing multiple characteristics of an individual from one fingerprint without additional laborious processes. The quick and fairly straightforward methods in this experiment have the potential to be utilized by law enforcement on-site without the need for intensive training or scientific knowledge.